Ib qho ntawm cov khoom tseem ceeb tshaj plaws ntawm txhua yam kabmob muaj sia yog kev hloov pauv, uas cuam tshuam txog cov txheej txheem hloov pauv hauv ntiaj teb, nrog rau kev txuag ntawm hom kev sib txawv ntawm nws. Qhov tsawg tshaj plaws ntawm cov noob caj noob ces yog cov noob - cov txheej txheem ntawm DNA molecule lub luag haujlwm rau kev xa cov ntaub ntawv keeb kwm cuam tshuam nrog ib qho kev zoo ntawm lub cev. Nyob ntawm seb qhov degree ntawm qhov tshwm sim, qhov tseem ceeb thiab cov noob caj noob ces yog qhov txawv. Ib tug yam ntxwv feature ntawm dominant units yog lub peev xwm los "suppress" recessive sawv daws yuav, muaj ib tug txiav txim zoo ntawm lub cev, tiv thaiv lawv los ntawm tshwm sim nyob rau hauv thawj tiam. Txawm li cas los xij, nws yuav tsum tau muab sau tseg tias nrog rau kev ua tiav, kev ua tiav tsis tiav yog pom, nyob rau hauv uas cov noob tseem ceeb tsis tuaj yeem cuam tshuam tag nrho cov kev tshwm sim ntawm recessive thiab overdominance, uas muab rau kev tshwm sim ntawm cov cim qhia nyob rau hauv ib daim ntawv muaj zog tshaj nyob rau hauv. homozygous kab mob. Nyob ntawm seb qhov twg allelic (uas yog, lub luag haujlwm rau kev loj hlob ntawm tib yam zoo) noob tau txais los ntawm niam txiv cov tib neeg, cov kab mob heterozygous thiab homozygous yog qhov txawv.
Definitionhomozygous kab mob
Homozygous kab mob yog cov khoom ntawm cov tsiaj qus uas muaj ob yam zoo tib yam (tseem ceeb lossis rov ua dua) cov noob rau ib lossis lwm qhov zoo. Ib qho tshwj xeeb ntawm cov tiam tom ntej ntawm homozygous cov tib neeg yog lawv tsis muaj kev sib cais ntawm cov cim thiab lawv qhov sib xws. Qhov no feem ntau piav qhia los ntawm qhov tseeb tias genotype ntawm homozygous kab mob muaj tsuas yog ib hom gametes, qhia los ntawm tsab ntawv loj thaum nws los txog rau qhov tseem ceeb, thiab tsab ntawv me me thaum xa mus rau cov khoom lag luam. Cov kab mob Heterozygous yog qhov txawv ntawm qhov tseeb tias lawv muaj cov noob sib txawv, thiab, raws li qhov no, tsim ob hom gametes. Homozygous kab mob uas yog recessive rau lub ntsiab alleles yuav raug xaiv raws li aa, bb, aabb, thiab lwm yam. Raws li, homozygous kab mob uas tseem ceeb hauv alleles muaj cai AA, BB, AABB.
Patterns ntawm qub txeeg qub teg
Hla ob hom kab mob heterozygous, uas nws cov genotypes tuaj yeem raug xaiv raws li Aa (qhov twg A yog ib qho tseem ceeb thiab ib tug yog ib tug recessive gene), ua rau nws muaj peev xwm kom tau nrog sib npaug qhov tshwm sim plaub sib txawv ua ke ntawm gametes (genotype variant) nrog a 3:1 faib los ntawm phenotype. Nyob rau hauv cov ntaub ntawv no, lub genotype yog to taub raws li tag nrho cov noob uas muaj cov diploid txheej ntawm ib tug tshwj xeeb cell; nyob rau hauv lub phenotype - ib qho system ntawm sab nraud nrog rau cov yam ntxwv ntawm lub cev nyob rau hauv nqe lus nug.
Dihybrid hla thiab nws cov yam ntxwv
Cia peb xav txog cov qauv ntsig txognrog crossbreeding txheej txheem uas homozygous kab mob koom nrog. Nyob rau hauv tib rooj plaub, yog hais tias muaj ib tug dihybrid los yog polyhybrid hla, tsis hais txog ntawm qhov zoo ntawm cov qub txeeg qub teg, splitting tshwm sim nyob rau hauv ib tug ratio ntawm 3: 1, thiab txoj cai no siv tau rau ib tug xov tooj ntawm lawv. Hla tib neeg ntawm tiam thib ob nyob rau hauv rooj plaub no tsim plaub hom phenotypes ntawm qhov piv ntawm 9: 3: 3: 1. Nws yuav tsum raug sau tseg tias txoj cai no siv tau rau homologous khub ntawm chromosomes, kev sib cuam tshuam ntawm cov noob nyob rau hauv uas tsis tau ua.
